Field
Embodiments of the disclosure relate generally to the field of structural systems for aircraft and more particularly to spars having offset webs to accommodate fittings or other structural limitations within low profile chord designs.
Background
Widespread use of composite structural systems with their associated high strength in aircraft has allowed tailoring of very thin cross-sections in aerodynamic surfaces with spars and other structure having reduced depth. However, in many cases, structural fittings, attachment limitations or other requirements are difficult to fit within the thin sections. In actuated surfaces with high loading, excessive moment arms may be required if fittings are placed in a standard structural arrangement within the thin sections. In addition it usually advantageous to locate the spar as close to the hinge line as possible. This creates challenges when attempting to locate fittings and maintain adequate space for joints.
It is therefore desirable to provide a structural design for spars used in such thin structures which allows more room to bolt the highly loaded actuator fittings or otherwise accommodate structural requirements without compromising the actuator fitting joint, compromising the repair capability, moving the spar within the design or otherwise aggravating hinge offsets and hinge loads, or segmenting the spar.